1. Field of the Invention
This invention relates generally to a process and an apparatus for producing metallic copper and, more specifically, to an electrolytic process and apparatus for producing metallic copper from a copper-containing waste material which copper may be in the form of a metal or a copper compound.
2. Description of Prior Art
The demand for saving of resources and protection of environment becomes an important, urgent problem. Copper is one of the most important metal and many studies have been made for the recovery of copper from copper-containing waste materials. Conventionally, recovery of copper from copper-containing waste materials has been made in a process of producing copper from copper ores by smelting. It is, however, impossible to increase the amount of the copper-containing waste material to be treated together with the copper ores. Another known method of recovering copper from copper-containing waste materials is a wet process in which the waste materials are treated with acid such as sulfuric acid or hydrochloric acid. With this process, not only copper but also various other metals are bleached in the acid solution so that it is necessary to separate a copper compound from other metal compounds in order to increase the purity of the recovered copper.
An electrolytic winning process is an effective method of recovering high purity copper metal from a copper-containing solution. This process, in which a Cu(II) ion electrolyte solution is energized to form metallic copper on the cathode and oxygen on the anode, consumes much electric energy to perform the electrolysis.